I. Field of the Invention
This invention relates generally to locking mechanisms and relates particularly to an apparatus which is locked within the eye of a trailer tongue to prevent the unauthorized movement of the trailer.
II. Description of the Prior Art
There are a number of locks made to secure one item within another to prevent unauthorized use or unauthorized access using a cylinder having tumblers operated by a key. This structure is revealed in U.S. Pat. Nos. Feller, 2,742,726; Kruschwitz, 2,791,976; and Jacobi, 1,982,831.
In U.S. Pat. No. Hudson, 3,844,143, a pintle hook locking device for an eye of a trailer tongue is revealed. This lock requires a separate adjustment for pintle size and provides no protection for the lock cylinder or for forced removal.
No prior device known to me provides the combination of attributes of the present invention, namely, a simple strong attachment means providing automatic sizing for a number of ring sizes, continued positive locking even upon lock cylinder removal and lock cylinder guard means.